I'm wondering if my 80 year old dad might have dementia or Alzheimer's.

My 80 year old dad was sent hospital he was talking out head got to hospital he was having heart problems and a UTI. He was trying to pull his clothes off and pull tubes out. He was in bed that whole 3 weeks. He was sent to Rehab. After 3 months he's still not walking much and was incontinent. He has days he thinks he's at work, he hasn't worked in over 5 years. He gets upset and no body no were at that not true. He wants to go home we tried it for a week he would stand to help my brother. Mentally he was more confused and would get angry and push my brother out the way. We decided that it be better to take him back to nursing home. Im wondering if he might have dementia or Alzheimers what do you think.